Setup
8
Centering
: Although the condenser comes pre-centered you may find it necessary to
check it occasionally. A simple method for centering is as follows:
1
2
3
All Models
Figure 5
Figure 6
4
Figure 8
70-80%
Figure 7a
Figure 7b
Figure 7c
Figure 7d
Vertical Focusing
: The condenser can be raised and lowered with the substage
adjustment knob to focus the light for optimal illumination.
Aperture Iris Diaphragm Adjustment
: To achieve the best contrast, resolution, and
depth of field, the aperture diaphragm should be set to approximately 70-80% of the field
(figure 8) to match the objective’s numerical aperture. Adjust the aperture iris diaphragm
with the aperture iris diaphragm lever (figure 6a) located at the bottom of the condenser.
Field Iris Diaphragm Adjustment
: The field diaphragm can be used to limit unwanted
peripheral light from entering the condenser and interfering with the image quality.
[a]
Substage Adjustments
• Rotate the nosepiece until the 10X objective is in the light path. For phase contrast
models set the phase annulus turret to the “0” position.
• Raise the substage assembly fully by turning the substage adjustment knob
counter-clockwise. Be careful not to crash the condenser lens into the objectives.
•
Open the Kohler field iris diaphragm to the largest setting by rotating the adjustment
ring (figure 5a) clockwise.
•
Slide the aperture diaphragm lever (figure 6a) to the right to close the aperture iris.
•
Closing the aperture diaphragm will reduce the field so that a small white hexagon
is visible within a black field (figure 7a). Remove one of the eyepieces and view
the image directly through the empty eyetube. Focus the hexagon by adjusting the
substage adjustment knob. This white hexagon should be centered in the black
field. If not, using a 1.5mm hex wrench first loosen the two condenser centering
screws located at the rear of the condenser mount, then reposition the condenser
until the iris is properly centered within the black field (figure 7b). Finally, tighten the
condenser centering screws back down.
•
Fine tune by opening the aperture iris diaphragm until the white hexagon almost fills
the entire field (figure 7c), and then readjust (figure 7d) by using the instructions in
the previous step. After centering the condenser, open the aperture iris diaphragm
slightly wider than the field of view.
[a]
